Harnessing Microbiomes for Global Nitrogen Cycle Management

One globally important function microbiomes perform for society is managing the biogeochemical nitrogen (N) cycle. Microorganisms catalyze all major steps in the N cycle, such as converting nitrogen gas into useable nutrients (fixation) and the recycling of nitrogen compounds in biomass, soils, and waters back to the atmosphere.

Recently, population growth and urbanization have created an imbalance in the nitrogen cycle, resulting in hundreds of oxygen deplete “dead zones” in coastal waters and toxic algal blooms in freshwater bodies worldwide. The problem has become so serious that the National Academy of Engineering has listed restoring balance to the N cycle as a grand challenge for the 21st century, which will require managing key microbiome interactions that drive N cycling in natural and engineered ecosystems.

N cycling microbes are widely known for their sensitivity to environmental conditions and for their intimate relationships with other microbes. However, no quantitative framework exists for understanding and predicting how microorganisms interact with their physical environment and with other microorganisms. The project will develop an effective set of computational and experimental tools that can quantify and predict the concentration and turnover rates of intracellular and extracellular metabolites (i.e. fluxes) in microbial communities.

This project also seeks to harness microbiome functions for restoring balance to the N cycle. The researchers will develop a systems biology approach that looks at two organisms — Nitrospira nitrosa and Brocadia sinica – and how to remodel their physiology in response to changing environmental conditions and microbe-microbe interactions.